Wireless Communication Method of Selecting an Enhanced Uplink Transport Format Combination

ABSTRACT

Methods of selecting an enhanced uplink (EU) transport format combination (E-TFC) are disclosed. A maximum number of bits of scheduled data for an upcoming transmission may be determined, wherein the highest value is lower or equal to: 
     
       
         
           
             
               
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     where SG is a serving grant, L e,ref  is the number of EU dedicated physical data channels (E-DPDCHs) used for a selected reference E-TFC, K e,ref  is the number of data bits of the reference E-TFC, Δ harq  is a hybrid automatic repeat request (HARM) offset for a specific data flow to be transmitted as signaled by higher layers, and A ed,ref  is a ratio derived from a parameter ΔE-DPDCH signaled by higher layers for the selected reference E-TFC.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/210,049 filed Aug. 15, 2011, now allowed, which claims priority ofU.S. application Ser. No. 11/773,579 filed Jul. 5, 2007, now issued asU.S. Pat. No. 8,000,291 on Aug. 16, 2011, which claims the benefit ofU.S. Provisional Application No. 60/818,848 filed Jul. 6, 2006. Theseapplications are incorporated by reference as if fully set forth.

This application is related to U.S. application Ser. No. 11/408,415filed on Apr. 21, 2006, now issued as U.S. Pat. No. 8,116,292 on Feb.14, 2012, which is incorporated by reference as if fully set forth.

FIELD OF INVENTION

The present invention is related to wireless communications. Moreparticularly, the present invention is related to a method ofdetermining a maximum number of bits of scheduled data for an upcomingtransmission and selecting enhanced uplink (EU) transport formatcombinations (E-TFCs).

BACKGROUND

In a Third Generation (3G) cellular system, such as the system 100 shownin FIG. 1, EU provides improvements to uplink (UL) data throughput andtransmission latency. The system 100 includes a Node-B 102, a radionetwork controller (RNC) 104 and a wireless transmit/receive unit (WTRU)106.

As shown in FIG. 2, the WTRU 106 includes a protocol architecture 200which includes higher layers 202 and an EU medium access control (MAC),(MAC-e) 206, used to support EU operation between a dedicated channelMAC, (MAC-d) 204, and a physical layer (PHY) 208. The MAC-e 206 receivesdata for EU transmission from channels known as MAC-d flows. The MAC-e206 is responsible for multiplexing data from MAC-d flows into MAC-eprotocol data units (PDUs) for transmission, and for selecting proper EUtransport format combinations (E-TFCs) for EU transmissions.

To allow for EU transmissions, physical resource grants are allocated tothe WTRU 106 by the Node-B 102 and the RNC 104. WTRU UL data channelsthat require fast dynamic channel allocations are provided with fast“scheduled” grants provided by the Node-B 102, and channels that requirecontinuous allocations are provided with “non-scheduled” grants by theRNC 104. The MAC-d flows provide data for UL transmission to the MAC-e206. The MAC-d flows are either configured as scheduled or non-scheduledMAC-d flows.

An SG is the grant for scheduled data, (i.e., a “scheduled grant”). A“non-scheduled grant” is the grant for non-scheduled data. The SG is thepower ratio that is converted to a corresponding amount of scheduleddata that can be multiplexed, thus resulting in the scheduled datagrant.

The RNC 104 configures non-scheduled grants for each MAC-d flow usingradio resource control (RRC) procedures. Multiple non-scheduled MAC-dflows can be configured simultaneously in the WTRU 106. Thisconfiguration is typically performed upon radio access bearer (RAB)establishment, but may be reconfigured when necessary. The non-scheduledgrant for each MAC-d flow specifies the number of bits that can bemultiplexed into a MAC-e PDU. The WTRU 106 is then allowed to transmitnon-scheduled transmissions up to the sum of non-scheduled grants, ifmultiplexed in the same transmission time interval (TTI).

Based on scheduling information sent in rate requests from the WTRU 106,the Node-B 102 dynamically generates scheduling grants for scheduledMAC-d flows. Signaling between the WTRU 106 and the Node-B 102 isperformed by fast MAC layer signaling. The scheduling grant generated bythe Node-B 102 specifies the maximum allowed EU dedicated physical datachannel (E-DPDCH)/dedicated physical control channel (DPCCH) powerratio. The WTRU 106 uses this power ratio and other configuredparameters to determine the maximum number of bits that can bemultiplexed from all scheduled MAC-d flows into a MAC-e PDU.

Scheduled grants are “on top of” and mutually exclusive of non-scheduledgrants. Scheduled MAC-d flows can not transmit data using anon-scheduled grant, and non-scheduled MAC-d flows can not transmit datausing a scheduled grant.

The EU transport format combination set (E-TFCS) comprising all possibleE-TFCs is known to the WTRU 106. For each EU transmission, an E-TFC isselected from a set of supported E-TFCs within the E-TFCS.

Since other UL channels take precedence over EU transmissions, the poweravailable for EU data transmission on E-DPDCH is the remaining powerafter the power required for DPCCH, dedicated physical data channel(DPDCH), high speed dedicated physical control channel (HS-DPCCH) and EUdedicated physical control channel (E-DPCCH) is taken into account.Based on the remaining transmit power for EU transmission, blocked orsupported states of E-TFCs within the E-TFCS are continuously determinedby the WTRU 106.

Each E-TFC corresponds to a number of MAC layer data bits that can betransmitted in an EU TTI. Since there is only one MAC-e PDU per E-TFCthat is transmitted in each EU TTI, the largest E-TFC that is supportedby the remaining power defines the maximum amount of data, (i.e., thenumber of bits), that can be transmitted within a MAC-e PDU.

Multiple scheduled and/or non-scheduled MAC-d flows may be multiplexedwithin each MAC-e PDU based on absolute priority. The amount of datamultiplexed from each MAC-d flow is the minimum of the current scheduledor non-scheduled grant, the available MAC-e PDU payload from the largestsupported TFC, and the data available for transmission on the MAC-dflow.

Within the supported E-TFCs, the WTRU 106 selects the smallest E-TFCthat maximizes the transmission of data according to the scheduled andnon-scheduled grants. When scheduled and non-scheduled grants are fullyutilized, available MAC-e PDU payload is fully utilized, or the WTRU 106has no more data available and allowed to be transmitted, MAC-e PDUs arepadded to match the next largest E-TFC size. This multiplexed MAC-e PDUand corresponding TFC are passed to the physical layer for transmission.

The SGs and non-SGs specify the maximum amount of data that can bemultiplexed from specific MAC-d flows into MAC-e PDUs each EU TTI. Sincethe scheduled grants are based on the E-DPDCH/DPCCH ratio, the number ofdata bits allowed to be multiplexed per MAC-e PDU can not be explicitlycontrolled only to allow certain sizes which match the limited number ofdata sizes of the supported E-TFCs within the E-TFCS.

The remaining transmit power for EU data transmission determines thelist of supported E-TFCs within the E-TFCS. Since the supported E-TFCsare determined from a limited number of E-TFCs in the TFCS, thegranularity of allowed MAC-e PDU sizes will not allow for all possibleMAC-d flow and MAC-e header combinations. Therefore, since the amount ofMAC-d flow data allowed by the grants to be multiplexed into a MAC-e PDUwill frequently not match the size of one of the supported E-TFCs,padding will be applied to the MAC-e PDU to match the smallest possibleE-TFC size within the list of supported E-TFCs.

It is expected that when EU cells are operating at maximum capacity, theMAC-e PDU multiplexing is frequently limited by the SGs and non-SGs, andnot limited by the largest supported E-TFC or the WTRU EU data availablefor transmission. In this case, depending on the granularity ofspecified E-TFCs within the E-TFCS padding required to match theselected E-TFC may exceed the multiplexing block size of MAC-d flow dataincluding associated MAC-e header information. In this case, theeffective data rate is unnecessarily reduced from what is allowed by theselected E-TFC and the physical resources required for its transmission.

FIG. 3 illustrates a MAC-e PDU 300. A MAC-e PDU header 302 and MAC-dflow data 304 allowed by scheduling and non-scheduling grants aremultiplexed. Among a set of supported E-TFCs, the WTRU 106 selects thesmallest E-TFC from a list of supported E-TFCs that is larger than MAC-ePDU header 302 and MAC-d flow data 304. Padding 306 is then applied tothe MAC-e PDU to match the selected E-TFC size. However, the padding 306may exceed the multiplexing block size of MAC-d flow data. In this case,physical resources used in the EU transmission are under utilized andthe effective WTRU data rate is unnecessarily reduced.

MAC-e PDU multiplexing logic provides more efficient data multiplexingand improved radio resource utilization for the cases where MAC-e PDUmultiplexing is limited by scheduled and/or non-scheduled grants, andnot limited by the largest supported E-TFC or available EU data fortransmission. The amount of data allowed to be multiplexed from MAC-dflows into MAC-e PDUs according to the scheduled and non-scheduledgrants is either increased or decreased to more closely match the nextsmaller or next larger E-TFC size relative to the amount of data allowedto be multiplexed by the scheduled and non-scheduled grants.

FIG. 4 is a flow diagram of a process 400 for generating MAC-e PDUs. Instep 405, a WTRU receives a scheduled data grant from a Node-B and/ornon-scheduled grants from an RNC. In step 410, an E-TFC transport blocksize is selected based on the amount of data allowed to be multiplexedaccording to the scheduled and non-scheduled grants. In step 415, themaximum amount of scheduled and/or non-scheduled data allowed to betransmitted according to the scheduled and non-scheduled grants isquantized so that the amount of data multiplexed into each MAC-e PDUmore closely matches the selected E-TFC transport block size.

FIG. 5 is a flow diagram of a process 500 for generating MAC-e PDUs. Instep 505, a WTRU receives a scheduled data grant from a Node-B and/ornon-scheduled grants from an RNC. In step 510, an E-TFC transport blocksize is selected based on the amount of data allowed to be multiplexedaccording to the scheduled and non-scheduled grants. In step 515, theamount of buffered WTRU data allowed to be multiplexed by the at leastone grant is quantized so that the sum of scheduled and non-scheduleddata (including MAC header and control information) multiplexed intoeach EU MAC-e PDU more closely matches the selected E-TFC transportblock size.

Alternatively, granularity of E-TFC sizes is defined within the E-TFCSso that the difference between E-TFC sizes is not greater than one MAC-dPDU and the associated MAC-e header overhead. E-TFCs are defined foreach possible MAC-d flow multiplexing combination and associated MAC-eheader overhead. By optimizing the E-TFCS in this way, the paddingrequired after MAC-d flow data is multiplexed according to the scheduledand non-scheduled grants will not exceed the size of possible MAC-d flowmultiplexing block sizes.

FIG. 6 is a flow diagram of a process 600 for generating a MAC-e PDU. Alargest E-TFC is selected from a set of supported E-TFCs that is smallerthan the size of MAC-d flow data and MAC-e control signaling allowed bycurrent grants 602. As a result, the selected E-TFC permits a decreasedamount of data to be multiplexed onto the MAC-e PDU relative to theamount allowed by the grants, to more closely match the largest E-TFCsize that is smaller than the amount required by scheduled andnon-scheduled grants. The MAC-d flow data (scheduled and/or nonscheduled) is multiplexed into a MAC-e PDU in accordance with anabsolute priority until no more MAC-d flow data blocks can be addedwithin the limit of the selected E-TFC 604. The MAC-e PDU is padded tomatch the selected E-TFC size 606.

FIG. 7 shows conventional uplink spreading and gain factor usage forhigh speed uplink power access (HSUPA). The power of the E-DPCCH and theE-DPDCH(s) is set relative to the DPCCH, such that gain factors are usedfor scaling the uplink channels relative to each other. As shown in FIG.7, the gain factors are applied individually for E-DPCCH and eachE-DPDCH. β_(ec) is the gain factor for the E-DPCCH and β_(ed,k) is thegain factor for the E-DPDCH(s). The WTRU derives these gain factors fromhigher layer signaling.

The E-DPCCH is scaled with the gain factor β_(ec), which is given by:

β_(ec)=β_(c) ·A _(ec);  Equation (1)

where β_(c) is the gain factor of the DPCCH. β_(c) is either signaled byhigher layers to the WTRU, or is computed. The ratio A_(ec) is derivedfrom the parameter ΔE-DPCCH signaled by higher layers, (e.g., at callsetup). Table 1 shows the meaning of the signaled values for ΔE-DPCCH.The WTRU will scale the E-DPCCH in relation to the DPCCH according tothe quantized amplitude ratio.

TABLE 1 Signaled Values for Quantized amplitude ratios ΔE-DPCCH A_(ec =)β_(ec /) β_(c) 8 30/15 7 24/15 6 19/15 5 15/15 4 12/15 3  9/15 2  8/15 1 6/15 0  5/15

During compressed frames, the E-DPCCH gain factor β_(ec) needs to bescaled. This is performed in order to avoid that the E-DPCCH power isincreased by the offset that is applied to the DPCCH during compressedframes. The uplink DPCCH slot formats that have TFCI bits contain fewerpilot bits than the formats for normal (non-compressed) mode. The reasonfor this is that the number of TFCI bits is always the same during aframe to ensure robust transport format detection. Therefore, in orderto keep the same channel quality, the energy of the pilot must be keptequal, and the power of the DPCCH is therefore increased by thefollowing factor: N_(pilot,N)/N_(pilot,C).

Therefore, if a 2 ms TTI overlaps with a compressed frame:

$\begin{matrix}{{\beta_{ec} = {\beta_{c,C,j} \cdot A_{ec} \cdot \sqrt{\frac{N_{{pilot},C}}{N_{{pilot},N}}}}};} & {{Equation}\mspace{14mu} (2)}\end{matrix}$

where β_(c,C,j) is a beta factor for DPCCH in compressed frames for thej^(th) transport format combination (TFC) such that β_(c,C,j)=1 when noDPDCH is configured, N_(pilot,c) is the number of pilot bits per slot onDPCCH in compressed frames, and N_(pilot,N) is the number of pilot bitsper slot in non-compressed frames.

If a 10 ms TTI overlaps with a compressed frame, the E-DPCCH gain factorβ_(ec) is additionally scaled (increased) to take into account that lessslots are available for transmission during this frame. In order to geta good transmission quality, the transmitted energy per information bitis the same, independent of whether compressed mode is used in a frameor not. Therefore, β_(ec) is additionally scaled with the factor15/N_(slots,C):

$\begin{matrix}{{\beta_{ec} = {\beta_{c,C,j} \cdot A_{ec} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},C} \cdot N_{{pilot},N}}}}};} & {{Equation}\mspace{14mu} (3)}\end{matrix}$

where N_(slots,C) is the number of non-discontinuous transmission(non-DTX) slots in this compressed frame.

As shown in FIG. 7, there can be one or more E-DPDCH(s), and each ofthem is scaled with its own gain factor. The gain factors may vary onradio frame basis or sub-frame basis depending on whether the E-DCH TTIis 10 ms or 2 ms, respectively. The gain factor β_(ed,k) for the kthE-DPCCH is determined by the transport format combination on E-DCH(E-TFC) carried in this TTI, and depending on the hybrid automaticrepeat request (HARD) profile for the data carried in this TTI. TheE-TFC describes the size of the transport block carried in a TTI. Thisparameter therefore influences the required transmission power.

For each data flow (MAC-d flow), higher layers can configure anindividual HARQ profile. The HARQ profile includes the power offset andmaximum number of HARQ retransmissions to use for this MAC-d flow. Thiscan be used to fine-tune operating points for different data flows. TheWTRU determines the gain factor β_(ed,k) based on parameters signaled byhigher layers, (e.g., at call setup).

First, a “reference E-TFC” needs to be determined in the WTRU for theE-TFC carried in the regarded TTI. A list of reference E-TFCs containingup to 8 reference E-TFCs is signaled by higher layers. The referenceE-TFC is selected as close as possible to the regarded E-TFC. Then, areference gain factor β_(ed,ref) is determined for the selectedreference E-TFC as follows:

β_(ed,ref)=β_(c) ·A _(ed,ref);  Equation (4)

where B is the gain factor of the DPCCH. The ratio A_(ed,ref) is derivedfrom the parameter ΔE-DPDCH signaled by higher layers for the selectedreference E-TFC. Table 2 shows the meaning of the signaled values forΔE-DPDCH. The reference E-TFC concept is used in order to avoid thesignaling overhead which would result from signaling a ΔE-DPDCH valuefor all possible E-TFC values.

However, this reference gain factor cannot directly be used for scalingthe E-DPDCHs, since the reference E-TFC does not reflect the actualE-TFC in terms of number of data bits contained and number of E-DPDCHsrequired for transmission. Furthermore, the HARQ profile needs to beconsidered.

TABLE 1 Signaled Values for Quantized amplitude ratios ΔE-DPCCHA_(ed,ref =) β_(ed /) β_(c) 29 168/15  28 150/15  27 134/15  26 119/15 25 106/15  24 95/15 23 84/15 22 75/15 21 67/15 20 60/15 19 53/15 1847/15 17 42/15 16 38/15 15 34/15 14 30/15 13 27/15 12 24/15 11 21/15 1019/15 9 17/15 8 15/15 7 13/15 6 12/15 5 11/15 4  9/15 3  8/15 2  7/15 1 6/15 0 15/15

Therefore, for the E-TFC to be transmitted in the TTI underconsideration (the j^(th) E-TFC), a temporary variable β_(ed,j,harq) iscomputed as follows:

$\begin{matrix}{{\beta_{{ed},j,{harq}} = {\beta_{{ed},{ref}}\sqrt{\frac{L_{e,{ref}}}{L_{e,j}}}{\sqrt{\frac{K_{e,j}}{K_{e,{ref}}}} \cdot 10^{\Delta \; {{harq}/20}}}}};} & {{Equation}\mspace{14mu} (5)}\end{matrix}$

where L_(e,ref) is the number of E-DPDCHs used for the reference E-TFC,L_(e,j) is the number of E-DPDCHs used for the j^(th) E-TFC, K_(e,ref)is the number of data bits of the reference E-TFC, K_(e,j) is the numberof data bits of the j^(th) E-TFC, and Δ_(harq) is the HARQ offset forthe specific data flow to be transmitted (so called “MAC-d flow”) assignaled by higher layers (see Table 3).

TABLE 3 Signaling values for Power offset values Δ_(harq) Δ_(harq [dB])6 6 5 5 4 4 3 3 2 2 1 1 0 0L_(e,ref) and L_(e,j) represent “equivalent” number of physicalchannels. Normally they are equal to number of used E-DPDCHs except fortwo cases:

-   -   1) 2×SF2 case: L_(e,ref) and L_(e,j) should be 4 instead of 2;        and    -   2) 2×SF2+2×SF4 case: L_(e, ref) and L_(e,J) should be 6 instead        of 4.        Therefore, the calculated β_(ed,j,harq) must be scaled by a        factor of √2 for SF=2 codes. The unquantized gain factor        β_(ed,k,j,uq) is set to √2×β_(ed,j,harq) for E-DPDCHs using        spreading factor 2 and equal to β_(ed,j,harq) otherwise. The        ratio β_(ed,k,j,uq)/β_(C) is now quantized according to Table 4        to obtain the ratio β_(ed,k,)/β_(C).

TABLE 4 Quantized amplitude ratios β_(ed,k,)/β_(C) 168/15  150/15 134/15  119/15  106/15  95/15 84/15 75/15 67/15 60/15 53/15 47/15 42/1538/15 34/15 30/15 27/15 24/15 21/15 19/15 17/15 15/15 13/15 12/15 11/15 9/15  8/15  7/15  6/15  5/15

During compressed frames, the E-DPDCH gain factor β_(ed,k) needs to bescaled as follows. The factors applied for the scaling the E-DPDCH havebeen introduced already in the E-DPCCH section above.

For 2 ms TTI, the gain factor used for the j^(th) E-TFC in a compressedframe is given by:

$\begin{matrix}{{\beta_{{ed},C,j} = {\beta_{c,C,j} \cdot A_{ed} \cdot \sqrt{\frac{L_{e,{ref}}}{L_{e,j}}} \cdot \sqrt{\frac{K_{e,j}}{K_{e,{ref}}}} \cdot 10^{\Delta \; {{harq}/20}} \cdot \sqrt{\frac{N_{{pilot},C}}{N_{{Pilot},N}}}}};} & {{Equation}\mspace{14mu} (6)}\end{matrix}$

where βc,C,j is the DPCCH beta factor in compressed frames for j^(th)TFC (β_(c,C,j)=1 when no DPDCH is configured), N_(pilot,C) is the numberof pilot bits per slot on DPCCH in compressed frames, N_(pilot,N) is thenumber of pilot bits per slot in non-compressed frames, and N_(slots,C)is the number of DTX slots in this compressed frame.

For 10 ms TTI, the gain factor used for the j^(th) E-TFC in a compressedframe is given by:

$\begin{matrix}{{\beta_{{ed},C,j} = {\beta_{c,C,j} \cdot A_{ed} \cdot \sqrt{\frac{L_{e,{ref}}}{L_{e,j}}} \cdot \sqrt{\frac{K_{e,j}}{K_{e,{ref}}}} \cdot 10^{\Delta \; {{harq}/20}} \cdot \sqrt{\frac{15 \cdot N_{{pilot},C}}{N_{{slots},I} \cdot N_{{pilot},N}}}}};} & {{Equation}\mspace{14mu} (7)}\end{matrix}$

where β_(c,C,j) is the beta factor in compressed frames for the j^(th)TFC (=1 when no DPDCH is configured), N_(pilot,C) is the number of pilotbits per slot on DPCCH in compressed frames, N_(pilot,N) is the numberof pilot bits per slot in non-compressed frames, and N_(slots,I) is thenumber of non-DTX slots in the first frame used for transmitting thedata.

Note that in the 10 ms case, retransmissions on E-DPDCH also requirescaling when the corresponding initial transmission overlapped acompressed frame (but the frame with the retransmission does not). Whenthe E-DCH TTI is 10 ms and the current frame is not compressed, but is aretransmission for which the corresponding first transmission wascompressed, β_(ed,R,j) represents the gain factor that shall be appliedto the j^(th) E-TFC as follows:

$\begin{matrix}{{\beta_{{ed},R,j} = {\beta_{{ed},j} \cdot \sqrt{\frac{15}{N_{{slots},I}}}}};} & {{Equation}\mspace{14mu} (8)}\end{matrix}$

where β_(ed,j) is the gain factor used for the j^(th) E-TFC innon-compressed frames.

The prior art describes the principles by which an E-TFC selectionprocedure should follow, but fails to describe a specific method andapparatus for determining the actual SGP. Thus, although the prior artrequires the computation of an SGP, a particular method or apparatus forperforming such a computation is not described. Although more than oneapproach for computing SGP may exist, a method and apparatus forcomputing an optimum, (i.e., “maximum” or “highest priority”), SGP isdesired.

SUMMARY

Methods of selecting an enhanced uplink (EU) transport formatcombination (E-TFC) are disclosed. A maximum number of bits of scheduleddata for an upcoming transmission may be determined as

${K_{e,{ref}} \cdot \frac{S\; G}{L_{e,{ref}} \cdot A_{{ed},{ref}}^{2} \cdot 10^{\Delta \; {{harq}/10}}}},$

where SG is a serving grant, L_(e,ref) is the number of EU dedicatedphysical data channels (E-DPDCHs) used for a selected reference E-TFC,K_(e,ref) is the number of data bits of the reference E-TFC, Δ_(harq) isa hybrid automatic repeat request (HARM) offset for a specific data flowto be transmitted as signaled by higher layers, and A_(ed,ref) is aratio derived from a parameter ΔE-DPDCH signaled by higher layers forthe selected reference E-TFC.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding of the invention may be had from thefollowing description of a preferred embodiment, given by way of exampleand to be understood in conjunction with the accompanying drawingswherein:

FIG. 1 shows a 3G cellular system;

FIG. 2 shows an EU protocol architecture in a WTRU;

FIG. 3 illustrates a MAC-e PDU generation;

FIG. 4 is a flow diagram of a process for generating MAC-e PDUs byquantizing the maximum amount of scheduled and/or non-scheduled dataallowed to be transmitted;

FIG. 5 is a block diagram of a process for generating MAC-e PDUs byquantizing the maximum amount of non-scheduled data allowed to bemultiplexed;

FIG. 6 is a flow diagram of a process for generating a MAC-e PDU byreducing multiplexed data;

FIG. 7 shows conventional uplink spreading and gain factor usage forHSUPA;

FIGS. 8A-8D, taken together, are a flow diagram of a process for datatransmission in accordance with the present invention; and

FIG. 9 is a flow diagram of a process for scheduling information withoutdata in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereafter, the terminology “WTRU” includes but is not limited to a userequipment (UE), a mobile station, a fixed or mobile subscriber unit, apager, or any other type of device capable of operating in a wirelessenvironment. When referred to hereafter, the terminology “base station”includes but is not limited to a Node-B, a site controller, an accesspoint or any other type of interfacing device in a wireless environment.

The present invention provides a method and apparatus for determiningthe payload for a specific SG. Furthermore, the present inventionchooses a protocol data unit (PDU) size by checking all sizes in orderto maximize high priority data transmissions.

The maximum PDU is the maximum supported transport block (TB) size (orEU medium access control (MAC-e) PDU size) in the set of allowed E-TFCs.

The remaining available payload is the remaining amount of data thatfits in the maximum PDU.

The SGP size is the highest payload that may be transmitted according tothe SG and a selected power offset (PO).

The remaining non-scheduled payload is the remaining non-scheduled grantvalue (per MAC-d flow).

The non-scheduled payload is the sum, for all non-scheduled dedicatedMAC (MAC-d) flows, of MIN (“remaining non-scheduled payload”,non-scheduled available payload), (i.e., the smallest one of theremaining non-scheduled payload and the non-scheduled availablepayload).

The scheduled payload is the amount of data in the radio link control(RLC) buffer of all scheduled MAC-d flows that is allowed to bemultiplexed with the highest priority selected MAC-d flow.

Power offset attribute, (in frequency division duplex (FDD)) is signaledto a WTRU. The power offset attribute represents the power offsetbetween one or more E-DPDCHs and a reference E-DPD CH power level for agiven E-TFC. The power offset attribute is set to achieve the requiredquality of service (QoS) in this MAC-d flow when carried alone in aMAC-e PDU and subsequently in the corresponding coded compositetransport channel (CCTrCh) of an EU dedicated channel (E-DCH) type.Power offsets must be translated into Beta factors that are used in thebase band (BB) to adjust the relative power levels of UL code channelssuch as DPDCHs and DPCCH in wideband code division multiple access(W-CDMA) FDD before feeding it into the transmitter. The referenceE-DPDCH power offset is signaled to the WTRU for at least one referenceE-TFC. The SG is simply an indication of the maximum E-DPDCH to DPCCHpower ratio that the WTRU is allowed to use for scheduled data in thefollowing transmission. The SG is provided to the E-TFC selectionfunction to support the selection of the “best” format for the upcomingtransmission.

While respecting the overall constraint of compliance with the SG value,the primary goal of the present invention is to select all possiblepower setting combinations for a given E-TFC, (depending on which datais available), and find the one combination that would result in “most”data sent.

FIGS. 8A-8D, taken together, are a flow diagram of a data transmissionprocedure 800 in accordance with the present invention. In step 802, aMAC-d flow with a PO is selected that allows highest-priority data to betransmitted. When more than one MAC-d flow allows data of the samehighest priority to be transmitted, the selection of the MAC-d flow maybe performed randomly. In step 804, based on the MAC-d flow selected,the MAC-d flow(s) that can be multiplexed are identified and the MAC-dflow(s) that cannot be multiplexed are ignored. In step 806, based onthe PO selected, E-TFC restriction is performed and the maximumsupported payload, (i.e., maximum MAC-e PDU size), that can be sent inthe next transmission timing interval (TTI) is determined. In step 808,the “Remaining Available Payload” is set to the maximum supportedpayload. In step 810, if the upcoming transmission overlaps with acompressed mode (CM) gap on 10 ms TTI, the current SG is scaled down.

CM is special in that parts of the frame are sent at a higher power, ascompared to normal uncompressed frames. Therefore, the SG must be“scaled” to take the presence of CM into account, by serving as anumerical adjustment. The DPCCH power assumed for the SG in a compressedframe is the actual DPCCH power in the compressed frame minus the “pilotpower”.

In step 812, the scheduled grant payload (SGP) is set to the highestpayload that can be transmitted according to the SG and the selected POas follows:

$\begin{matrix}{{{S\; G} = {\left( \frac{\beta_{{ed},j,{harq}}}{\beta_{c}} \right)^{2}\frac{S\; G\; P}{TBsize}}};{and}} & {{Equation}\mspace{14mu} (9)} \\{{{S\; G\; P} = \frac{S\; G \times {TBsize} \times \beta_{c}^{2}}{\beta_{{ed},j,{harq}}^{2}}};} & {{Equation}\mspace{14mu} (10)}\end{matrix}$

where TBsize is the maximum supported payload (transport block size) andj is the considered TFC that supports the maximum supported payload. TheSG=MIN(SGP, TBsize). β_(c) is the gain factor of the DPCCH. Aspreviously disclosed:

$\begin{matrix}{{\beta_{{ed},{ref}} = {\beta_{c} \cdot A_{{ed},{ref}}}};{and}} & {{Equation}\mspace{14mu} (4)} \\{\beta_{{ed},j,{harq}} = {\beta_{{ed},{ref}}\sqrt{\frac{L_{e,{ref}}}{L_{e,j}}}{\sqrt{\frac{K_{e,j}}{K_{e,{ref}}}} \cdot {10^{\Delta \; {{harq}/20}}.}}}} & {{Equation}\mspace{14mu} (5)}\end{matrix}$

Thus, when β_(c)·A_(ed,raf) of Equation (4) is substituted in Equation(5) for β_(ed,ref):

$\begin{matrix}{{\beta_{{ed},j,{harq}}^{2} = {\beta_{c}^{2} \cdot A_{{ed},{ref}}^{2} \cdot \frac{L_{e,{ref}}}{L_{e,j}} \cdot \frac{K_{e,j}}{K_{e,{ref}}} \cdot 10^{{({\Delta \; {{harq}/20}})}^{2}}}};} & {{Equation}\mspace{14mu} (11)}\end{matrix}$where 10^((Δharq/20)) ² =10^(Δharq/10).  Equation (12)

In accordance with the present invention,

$\begin{matrix}{{{\frac{\beta_{c}^{2}}{\beta_{{ed},j,{harq}}^{2}} = {\frac{1}{A_{{ed},{ref}}^{2}} \cdot \frac{L_{e,j}}{L_{e,{ref}}} \cdot \frac{K_{e,{ref}}}{K_{e,j}} \cdot \frac{1}{10^{\Delta \; {{harq}/10}}}}};{and}}\begin{matrix}{{S\; G\; P} = {{\frac{S\; {G \cdot {TBSize}}}{1} \cdot \frac{1}{A_{{ed},{ref}}^{2}} \cdot \frac{L_{e,j}}{L_{e,{ref}}} \cdot \frac{K_{e,{ref}}}{k_{e,j}} \cdot \mspace{104mu} {Equation}}\mspace{14mu} (14)}} \\{\frac{1}{10^{\Delta \; {{harq}/10}}}} \\{= {{K_{e,{ref}} \cdot \frac{S\; G}{L_{e,{ref}} \cdot A_{{ed},{ref}}^{2} \cdot 10^{\Delta \; {{harq}/10}}} \cdot \mspace{149mu} {Equation}}\mspace{14mu} (15)}} \\{{\frac{{TBSize} \cdot L_{e,j}}{K_{e,j}}.}}\end{matrix}} & {{Equation}\mspace{14mu} (13)}\end{matrix}$

In accordance with one preferred embodiment of the present invention,the factor

$\frac{{TBSize} \cdot L_{e,j}}{K_{e,i}}$

will always result in the closest possible quantized value to 1 as partof the iterative procedure described above in the present invention, andthus

$\begin{matrix}{{S\; G\; P} = {K_{e,{ref}} \cdot {\frac{S\; G}{L_{e,{ref}} \cdot A_{{ed},{ref}}^{2} \cdot 10^{\Delta \; {{harq}/10}}}.}}} & {{Equation}\mspace{14mu} (16)}\end{matrix}$

This is easily seen when considering that L_(e,j) is the number ofE-DPDCHs used for the j^(th) E-TFC as described earlier.

For example, but not limited to this specific case, L_(e,j)=1 in thecase of HSUPA WTRU Category 1 where only 1 E-DPDCH with an SF notsmaller than 4 is possible. Because Ke,j is the number of data bits ofthe j^(th) E-TFC under consideration, the factor that maximizes thethroughput as described is when the factor TBSize/K_(e,j) is the closestpossible quantized value to 1 as a function of the configured E-TFCSs.

In other cases where L_(e,j) is not equal to 1, as a function of thenumber of E-DPDCHs and possibly their respective SFs as describedearlier, the SGP in Equations (15) and (16) will yield values that donot exceed a transport block size, (i.e., TBSize), that corresponds to ahigher reference E-TFC and that is not lower than the specific referenceE-TFC used in the computation, unless the specific reference E-TFC isthe smallest one.

Referring still to FIG. 8, in step 814, for each MAC-d flow with anon-scheduled grant, the “Remaining Non-scheduled Payload” is set to thevalue of the grant. In step 816, the “Non scheduled Payload” is set tothe sum of MIN (“Remaining Non-scheduled Payload”, non-scheduledavailable payload) for all non scheduled MAC-d flow(s).

If it is determined in step 818 that scheduling information needs to betransmitted, and if in step 820 the “Remaining Available Payload” isdetermined to be greater than the sum of the “Scheduled Grant Payload”,the “Non-scheduled Payload” and the size of the scheduling information,(i.e., the TB size can carry all of the data the WTRU can possiblysend), the sum of the “Scheduled Grant Payload”+“Non-scheduledPayload”+size of the scheduling information is quantized to the nextsmaller supported E-TFC (step 822). In step 824, the “Scheduled GrantPayload” is set to the quantized sum minus the “Non-scheduled Payload”and the size of the scheduling information. In step 826, the “RemainingAvailable Payload” is set to the supported payload in the next smallersupported E-TFC. In step 828, the size of the Scheduling Information issubtracted from the “Remaining Available Payload”.

If it is determined in step 818 that scheduling information does notneed to be transmitted, and if the “Remaining Available Payload” isdetermined in step 830 to be greater than the sum of the “ScheduledGrant Payload” and the “Non-scheduled Payload” (i.e., the TB size cancarry all of the data the WTRU can possibly send), the sum of the“Scheduled Grant Payload” and the “Non-scheduled Payload” is quantizedto the next smaller supported E-TFC (step 832), the “Scheduled GrantPayload” is set to the quantized sum minus the “Non-scheduled Payload”(step 834) and the “Remaining Available Payload” is set to the supportedpayload in the next smaller supported E-TFC (step 836).

Still referring to FIG. 8, one of a plurality of logical channels isselected based on an order of priority (step 838), and then steps840-850 are performed for the selected logical channel before loopingback to step 838 if it is determined in step 852 that there is at leastone more logical channel from which to select. In step 840, adetermination is made as to whether the selected logical channel belongsto a MAC-d flow with a non-scheduled grant.

If the determination of step 840 is positive, the “RemainingNon-scheduled Payload” corresponding to the MAC-d flow on which thislogical channel is mapped is considered (step 842), and an RLC PDU sizeis chosen from the allowed set in the selected logical channel to fillthe MAC-e PDU by choosing the PDU size that gives the most amount ofdata which is less than MIN(“Remaining Non-scheduled Payload”, AvailableData for this logical channel, “Remaining Available Payload”) (step844). In order to check which PDU size provides the largest amount ofdata, it is necessary to check for every size allowed. In step 846, thecorresponding bits if any are subtracted from the “Remaining AvailablePayload” and the “Remaining Non-scheduled Payload” (taking into accountthe MAC-e headers).

If the determination of step 840 is negative, an RLC PDU size is chosenfrom the allowed set in the selected logical channel to fill the MAC-ePDU by choosing the PDU size that gives the most amount of data which isless than MIN (“Scheduled Grant Payload”, Available Data for thislogical channel, “Remaining Available Payload”) (step 848). In order tocheck which PDU size provides the largest amount of data, it isnecessary to check for every size allowed. In step 850, thecorresponding bits if any are subtracted from the “Remaining AvailablePayload” and the “Scheduled Grant Payload” (taking into account theMAC-headers).

If it is determined in step 852 that there are no more logical channelsto select from, and if it is determined in step 854 that schedulinginformation needs to be transmitted, scheduling information is added tothe MAC-e PDU (step 856) and the smallest E-TFC that can carry theresulting MAC-e PDU is determined (step 858).

If it is determined in step 854 that scheduling information does notneed to be transmitted, the smallest E-TFC that can carry the resultingMAC-e PDU is determined (step 860) and if the padding allows schedulinginformation to be sent, it is added to the MAC-e PDU (step 862).Finally, in step 864, the maximum number of hybrid automatic repeatrequest (HARQ) transmissions is set to the maximum among the maximumnumber of HARQ transmissions of the HARQ profiles of the MAC-d flowsselected for transmissions.

FIG. 9 is a flow diagram of a data-less scheduling informationtransmission procedure 900 in accordance with the present invention. Ifin step 905 it is determined that scheduling information is to betransmitted without data, the “control-only” HARQ profile is selected(step 910), the MAC-e PDU is filled with the scheduling information(step 915) and the smallest E-TFC is selected (step 920). When thescheduling information is sent alone (no data), then the PO to be usedis the one configured by an RRC in the information element (IE) “PowerOffset for Scheduling Information” in the “E-DPDCH Info.” This is partof an RRC-layer signaled configuration information for enhanced UL,whereby the RNC signals parameters to the WTRU for setting up andrunning the e-MAC.

Although the features and elements of the present invention aredescribed in the preferred embodiments in particular combinations, eachfeature or element can be used alone without the other features andelements of the preferred embodiments or in various combinations with orwithout other features and elements of the present invention. Themethods or flow charts provided in the present invention may beimplemented in a computer program, software, or firmware tangiblyembodied in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) module.

1. A method of selecting an enhanced uplink (EU) transport formatcombination (E-TFC), the method comprising: determining a number ofscheduled data bits for an upcoming transmission, wherein the number ofscheduled data bits is derived at least from a serving grant multipliedby a transport block size of a j^(th) TFC, a β value associated with thej^(th) TFC, and a β_(c) value.
 2. The method of claim 1, wherein the βvalue associated with the j^(th) TFC and the β_(c) value are squared. 3.The method of claim 1, further comprising selecting a power offset (PO)for the upcoming transmission associated with a medium access control(MAC-d) flow that allows highest-priority data to be transmitted.
 4. Themethod of claim 1, further comprising: selecting a medium access control(MAC-d) flow; and identifying other MAC-d flows for which data can bemultiplexed.
 5. The method of claim 1, wherein the β_(c) value is a gainfactor related to a Dedicated Physical Control Channel (DPCCH).
 6. Awireless transmit/receive unit (WTRU) configured to select an enhanceduplink (EU) transport format combination (E-TFC), the WTRU configuredto: determine a number of scheduled data bits for an upcomingtransmission, wherein the number of scheduled data bits is derived atleast from a serving grant multiplied by a transport block size of aj^(th) TFC, a β value associated with the j^(th) TFC, and a β_(c) value.7. The WTRU of claim 6, wherein the β value associated with the j^(th)TFC and the β_(c) value are squared.
 8. The WTRU of claim 6, wherein theWTRU is further configured to select a power offset (PO) for theupcoming transmission associated with a medium access control (MAC-d)flow that allows highest-priority data to be transmitted.
 9. The WTRU ofclaim 6, wherein the WTRU is further configured to: select a mediumaccess control (MAC-d) flow; and identify other MAC-d flows for whichdata can be multiplexed.
 10. The WTRU of claim 6, wherein the β_(c)value is a gain factor related to a Dedicated Physical Control Channel(DPCCH).